U.S. patent application number 11/480968 was filed with the patent office on 2008-01-10 for method and device for scanning data for signatures prior to storage in a storage device.
Invention is credited to Laurence Hamid.
Application Number | 20080010682 11/480968 |
Document ID | / |
Family ID | 38894161 |
Filed Date | 2008-01-10 |
United States Patent
Application |
20080010682 |
Kind Code |
A1 |
Hamid; Laurence |
January 10, 2008 |
Method and device for scanning data for signatures prior to storage
in a storage device
Abstract
The present invention relates to a method and device for
scanning of data for signatures prior to storage. First data are
received at a storage device for storage therein. Upon receipt the
first data are stored in a temporary storage medium for storing
other than guaranteed previously scanned data. Using a processor of
the storage device, the first data are compared with at least a
predetermined signature and a comparison result is determined in
dependence thereupon. In dependence upon the comparison result the
first data are provided to the scanned data memory when the
comparison result is indicative of other than a match or the first
data are other than provided to the scanned data memory when the
comparison result is indicative of a match. The method and the
device according to the invention substantially reduce the risk
that a file infected with a computer virus is transferred from one
computer to another via a portable storage medium. In another
aspect of the invention, the method and the device according to the
invention prevents storage of sensitive data by unauthorized
persons.
Inventors: |
Hamid; Laurence; (Ottawa,
CA) |
Correspondence
Address: |
FREEDMAN & ASSOCIATES
117 CENTREPOINTE DRIVE, SUITE 350
NEPEAN, ONTARIO
K2G 5X3
omitted
|
Family ID: |
38894161 |
Appl. No.: |
11/480968 |
Filed: |
July 6, 2006 |
Current U.S.
Class: |
726/24 |
Current CPC
Class: |
G06F 21/80 20130101;
G06F 21/85 20130101; G06F 21/564 20130101; G06F 21/79 20130101 |
Class at
Publication: |
726/24 |
International
Class: |
G06F 12/14 20060101
G06F012/14 |
Claims
1. A method for storing data in a storage device comprising:
receiving, at the storage device, first data for being stored
within the storage device; storing the first data in a temporary
storage medium within the storage device, the temporary storage
medium for storing other than guaranteed previously scanned data;
using circuitry of the storage device comparing the first data with
at least a predetermined signature and determining a comparison
result in dependence thereupon; and, performing, in dependence upon
the comparison result, one of providing the first data for storage
within a scanned data memory of the storage device, the scanned
data memory for storing guaranteed previously scanned data therein,
when the comparison result is indicative of other than a match, and
other than providing the first data for storage within the scanned
data memory when the comparison result is indicative of a
match.
2. A method for storing data in a storage device as defined in
claim 1 wherein the at least a predetermined signature is
indicative of at least a computer virus, the method comprising
receiving at least an updated predetermined signature.
3. A method for storing data in a storage device as defined in
claim 2 comprising establishing secure communication in accordance
with a secure protocol for receiving the at least an updated
predetermined signature.
4. A method for storing data in a storage device as defined in
claim 3 wherein the secure communication is established with a
server for providing predetermined signatures.
5. A method for storing data in a storage device as defined in
claim 4 wherein the secure communication comprises symmetric key
encryption.
6. A method for storing data in a storage device as defined in
claim 5 wherein a symmetric key is provided by a trusted
source.
7. A method for storing data in a storage device as defined in
claim 6 comprising storing the key in a memory of the storage
device.
8. A method for storing data in a storage device as defined in
claim 4 wherein the secure communication comprises asymmetric key
encryption.
9. A method for storing data in a storage device as defined in
claim 8 wherein keys are provided by a trusted source.
10. A method for storing data in a storage device as defined in
claim 3 comprising: sending a request for receiving the at least an
updated predetermined signature, the request including data
indicative of a last update of the at least a predetermined
signature; and, storing the received the at least an updated
predetermined signature.
11. A method for storing data in a storage device as defined in
claim 10 wherein the request is sent in predetermined time
intervals.
12. A method for storing data in a storage device as defined in
claim 1 comprising deleting the first data when the comparison
result is indicative of a match.
13. A method for storing data in a storage device as defined in
claim 1 comprising repairing the first data when the comparison
result is indicative of a match.
14. A method for storing data in a storage device as defined in
claim 1 comprising storing the first data in a buffer memory, the
buffer memory for storing other than guaranteed previously scanned
data.
15. A method for storing data in a storage device as defined in
claim 14 comprising: generating message data indicating that a
computer virus has been detected; and, storing the message
data.
16. A method for storing data in a storage device as defined in
claim 1 comprising providing data indicative of a presence of the
circuitry prior to receipt of the first data.
17. A method for storing data in a storage device as defined in
claim 1 wherein the storage device comprises a first and a second
housing, the first housing containing the temporary storage medium
and the circuitry and the second housing containing the scanned
data memory, and wherein the first data are provided to the scanned
data memory via a first interface of the first housing in
electrical communication with a second interface of the second
housing.
18. A method for storing data in a storage device as defined in
claim 16 wherein the at least a predetermined signature is
indicative of at least a security level of the first data, the
method comprising deleting the first data when the comparison
result is indicative of a match.
19. A method for storing data in a storage device as defined in
claim 18 comprising generating message data indicating that the
first data have been prevented from storage.
20. A method for storing data in a storage device as defined in
claim 18 comprising receiving authorization data indicative of a
security level of a user of a host system in communication with the
storage device; and, selecting, in dependence upon the
authorization data, predetermined signatures corresponding to
security levels above the security level of the user.
21. A method for storing data in a storage device as defined in
claim 20 comprising: receiving second authorization data indicative
of a second security level of a user of a host system in
communication with the storage device; comparing the second
authorization data with the security level of the first data based
on the selected at least a predetermined signature; and, providing
the first data from the scanned data memory when the second
security level is one of equal to the security level of the first
data and higher than the security level of the first data.
22. A method for storing data in a storage device as defined in
claim 20 wherein receiving authorization data comprises receiving
biometric information from the user and determining the security
level of the user in dependence thereupon.
23. A method for storing data in a storage device as defined in
claim 21 wherein receiving second authorization data comprises
receiving biometric information from the user and determining the
second security level of the user in dependence thereupon.
24. A storage device comprising: a first port for receiving first
data for being stored within the storage device; a temporary
storage medium in communication with the first port for storing
other than guaranteed previously scanned data; a scanned data
memory for storing guaranteed previously scanned data therein;
circuitry in communication with the first port, the temporary
storage medium and the scanned data memory, the circuitry for: a)
comparing the first data with at least a predetermined signature
and determining a comparison result in dependence thereupon; and,
b) performing, in dependence upon the comparison result, one of
providing the first data for storage within the scanned data memory
when the comparison result is indicative of other than a match, and
other than providing the first data for storage within the scanned
data memory when the comparison result is indicative of a
match.
25. A storage device as defined in claim 24 comprising a signature
memory in communication with the circuitry for storing the at least
a predetermined signature.
26. A storage device as defined in claim 24 comprising second
memory in communication with the circuitry, the second memory
having stored therein executable commands for execution on the
circuitry, the circuitry when executing the commands performing a)
and b).
27. A storage device as defined in claim 24 comprising a buffer
memory in communication with the circuitry for storing other than
guaranteed previously scanned data prior scanning by the
circuitry.
28. A storage device as defined in claim 24 comprising an unscanned
data memory in communication with the first port for storing other
than guaranteed previously scanned data.
29. A storage device as defined in claim 27 comprising an internal
power source.
30. A storage device as defined in claim 24 wherein the storage
device is an internal storage device for being disposed in a host
system.
31. A storage device as defined in claim 30 wherein the internal
storage device is a hard-drive.
32. A storage device as defined in claim 24 wherein the storage
device is an external storage device for being coupled to an
external port of a host system.
33. A storage device as defined in claim 32 wherein the first port
is a serial port for coupling to a serial port of the host
system.
34. A storage device as defined in claim 33 wherein the serial port
is a USB port.
35. A storage device as defined in claim 32 wherein the external
storage device is at least one of an external hard-drive, an
internal CD device, an external CD device, and internal DVD device
or an external DVD device.
36. A storage device as defined in claim 32 wherein the external
storage device is a portable storage device.
37. A storage device as defined in claim 36 wherein the first port
is a serial port for coupling to a serial port of the host
system.
38. A storage device as defined in claim 37 wherein the serial port
is a USB port.
39. A storage device as defined in claim 36 wherein the portable
storage device is at least a USB memory storage key or a flash
memory card.
40. A storage device as defined in claim 36 comprising a biometric
input device in communication with the circuitry, the circuitry for
receiving biometric input data and for performing one of: providing
the biometric input data to a processor of the host system; and,
comparing the biometric input data with biometric data indicative
of a user and determining a security level of the user in
dependence thereupon.
41. A storage device as defined in claim 40 wherein the biometric
input device is at least one of a fingerprint imager, a voice
recognition device, a retinal imager, a facial recognition device
and a hand writing recognition device.
42. A coupler comprising: a first interface for coupling to a port
of a host system for receiving first data for being stored in a
scanned data memory of a portable storage device, the scanned data
memory for storing guaranteed previously scanned data therein; a
second interface for interfacing with the portable storage device;
a temporary storage medium in communication with the first
interface for storing other than guaranteed previously scanned
data; circuitry in communication with the first interface, the
temporary storage medium and the second interface, the circuitry
for: a) comparing the first data with predetermined signatures and
determining a comparison result in dependence thereupon; and, b)
performing, in dependence upon the comparison result, one of
providing via the second interface the first data for storage
within the scanned data memory when the comparison result is
indicative of other than a match, and other than providing the
first data for storage within the scanned data memory when the
comparison result is indicative of a match.
43. A coupler as defined in claim 42 wherein the first interface is
at least one of a serial interface and a parallel interface for
coupling to a communications port of the host system.
44. A coupler as defined in claim 43 wherein the serial interface
is a USB interface.
45. A coupler as defined in claim 42 wherein the second interface
is a USB interface for coupling to a USB memory storage key.
46. A coupler as defined in claim 45 comprising second memory in
communication with the circuitry, the second memory having stored
therein executable commands for execution on the circuitry, the
circuitry when executing the commands performing a) and b).
47. A coupler as defined in claim 46 comprising a biometric input
device in communication with the circuitry, the circuitry for
receiving biometric input data and for performing one of: providing
the biometric input data to a processor of the host system; and,
comparing the biometric input data with biometric data indicative
of a user and determining a security level of the user in
dependence thereupon.
48. A coupler as defined in claim 42 wherein the first interface is
designed for coupling to an expansion slot disposed in the host
system.
49. A coupler as defined in claim 48 wherein the first interface is
at least one of a serial interface and a parallel interface for
coupling to a communications port of the host system.
50. A coupler as defined in claim 49 wherein the serial interface
is a USB interface.
51. A coupler as defined in claim 50 wherein the second interface
is a USB interface for coupling to a USB memory storage key.
52. A coupler as defined in claim 42 wherein the second interface
comprises a mechanism for writing data into an optical storage
medium.
53. A storage medium having stored therein executable commands for
execution on a processor of a host system, the processor when
executing the commands performing: providing first data to a
storage device for storage therein when data from the storage
device have been received, the data being indicative of a presence
of a circuitry for: comparing the first data with at least a
predetermined signature and determining a comparison result in
dependence thereupon; and, performing, in dependence upon the
comparison result, one of providing the first data for storage
within a scanned data memory when the comparison result is
indicative of other than a match, and other than providing the
first data for storage within the scanned data memory when the
comparison result is indicative of a match; and, other than
providing the first data to the storage device in the absence of
data indicative of the presence of the circuitry.
Description
FIELD OF THE INVENTION
[0001] This invention relates to the field of computer safety and
in particular to a method and device for scanning data for
signatures prior to storage in a storage device.
BACKGROUND
[0002] With the proliferation of computers and computer networks
into all aspects of business and daily life--financial, medical,
education, government, and communications--the concern over
computer security is growing. A major issue in computer security is
the problem of computer viruses. A computer virus is generally a
manmade destructive computer program or code that is loaded onto a
computer system without the knowledge of the user. The computer
virus is often a self-replicating program that copies itself and
infects other programs and data files by modifying them or their
environment. The computer virus spreads from one computer to
another when an infected computer program or data file is taken to
the uninfected computer, for example, by a user sending it over a
network or carrying it on a portable storage medium. While some
computer viruses are intentionally destructive, for example,
deleting data, many other viruses are fairly benign. However, even
such viruses are dangerous as they are able to access systems,
potentially utilizing a large portion of the available resources
and possibly shutting down an infected computer system.
[0003] Many antivirus programs have become commercially available
for protection against viruses. Most commercially available
antivirus programs scan computer files to look for known viruses by
comparing the data of the computer file with signatures in a
dictionary of known viruses that the authors of the antivirus
software have identified. If some data in the computer file match a
signature of a virus identified in the dictionary, the antivirus
software takes one of the following actions: [0004] attempts to
repair the infected file by removing the virus from the file;
[0005] quarantines the infected file such that the file remains
inaccessible to other programs and its virus can no longer spread;
and, [0006] deletes the infected file. As is evident, the
signatures in the dictionary need to be updated on a regular basis.
The antivirus software typically examines files when a computer's
operating system creates, opens, closes, downloads, or e-mails
them. Furthermore, the antivirus software is usually scheduled to
scan all files on the computer's hard-drive on a regular basis.
However, this still leaves a loophole for spreading a computer
virus before a dictionary is updated.
[0007] With ever increasing storage capacity of portable storage
devices such as CDs, DVDs, and USB memory storage keys, manual file
transfer from one computer to another is substantially facilitated.
Unfortunately, this also increases the risk of transferring an
infected file from one computer to another.
[0008] Furthermore, the increasing storage capacity of USB memory
storage keys presents a significant security challenge for large
organizations. Their small size and ease of use allows unsupervised
visitors or unscrupulous employees to smuggle confidential data
with little chance of detection. To prevent this, some
organizations--particularly government departments and larger
corporations--forbid the use of USB memory storage keys, and
computers are configured to disable the mounting of USB memory
storage keys. Some organizations use a lower-tech security
solution, disconnecting USB ports inside the computer or filling
the USB ports with glue.
[0009] It would be highly desirable to overcome the drawbacks of
the present technology and to increase computer security.
SUMMARY OF THE INVENTION
[0010] It is, therefore, an object of embodiments of the invention
to provide a method and device for supporting scanning of data for
signatures prior to storage in a storage device.
[0011] It is an advantage of some embodiments of the invention to
provide a method and device for supporting scanning of data for
signatures prior to storage in a USB memory storage key.
[0012] In accordance with the present invention there is provided a
method for storing data in a storage device comprising: [0013]
receiving, at the storage device, first data for being stored
within the storage device; [0014] storing the first data in a
temporary storage medium within the storage device, the temporary
storage medium for storing other than guaranteed previously scanned
data; [0015] using circuitry of the storage device comparing the
first data with at least a predetermined signature and determining
a comparison result in dependence thereupon; and, [0016]
performing, in dependence upon the comparison result, one of
providing the first data for storage within a scanned data memory
of the storage device, the scanned data memory for storing
guaranteed previously scanned data therein, when the comparison
result is indicative of other than a match, and other than
providing the first data for storage within the scanned data memory
when the comparison result is indicative of a match.
[0017] In accordance with the present invention there is further
provided a storage device comprising: [0018] a first port for
receiving first data for being stored within the storage device;
[0019] a temporary storage medium in communication with the first
port for storing other than guaranteed previously scanned data;
[0020] a scanned data memory for storing guaranteed previously
scanned data therein; [0021] circuitry in communication with the
first port, the temporary storage medium and the scanned data
memory, the circuitry for: [0022] a) comparing the first data with
at least a predetermined signature and determining a comparison
result in dependence thereupon; and, [0023] b) performing, in
dependence upon the comparison result, one of providing the first
data for storage within the scanned data memory when the comparison
result is indicative of other than a match, and other than
providing the first data for storage within the scanned data memory
when the comparison result is indicative of a match.
[0024] In accordance with the present invention there is yet
further provided a coupler comprising: [0025] a first interface for
coupling to a port of a host system for receiving first data for
being stored in a scanned data memory of a portable storage device,
the scanned data memory for storing guaranteed previously scanned
data therein; [0026] a second interface for interfacing with the
portable storage device; [0027] a temporary storage medium in
communication with the first interface for storing other than
guaranteed previously scanned data; [0028] circuitry in
communication with the first interface, the temporary storage
medium and the second interface, the circuitry for: [0029] a)
comparing the first data with predetermined signatures and
determining a comparison result in dependence thereupon; and,
[0030] b) performing, in dependence upon the comparison result, one
of providing via the second interface the first data for storage
within the scanned data memory when the comparison result is
indicative of other than a match, and other than providing the
first data for storage within the scanned data memory when the
comparison result is indicative of a match.
[0031] In accordance with the present invention there is yet
further provided a storage medium having stored therein executable
commands for execution on a processor of a host system, the
processor when executing the commands performing: [0032] providing
first data to a storage device for storage therein when data from
the storage device have been received, the data being indicative of
a presence of a circuitry for: [0033] comparing the first data with
at least a predetermined signature and determining a comparison
result in dependence thereupon; and, [0034] performing, in
dependence upon the comparison result, one of providing the first
data for storage within a scanned data memory when the comparison
result is indicative of other than a match, and other than
providing the first data for storage within the scanned data memory
when the comparison result is indicative of a match; and, [0035]
other than providing the first data to the storage device in the
absence of data indicative of the presence of the circuitry.
BRIEF DESCRIPTION OF THE FIGURES
[0036] Exemplary embodiments of the invention will now be described
in conjunction with the following drawings, in which:
[0037] FIGS. 1a to 1d are simplified block diagrams illustrating a
first embodiment of a storage device supporting scanning of data
for signatures prior to storage according to the invention;
[0038] FIG. 2 is a simplified flow diagram illustrating a first
embodiment of a method for supporting scanning of data for
signatures prior to storage according to the invention;
[0039] FIG. 3 is a simplified block diagram illustrating a second
embodiment of a storage device supporting scanning of data for
signatures prior to storage according to the invention;
[0040] FIG. 4 is a simplified flow diagram illustrating a second
embodiment of a method for supporting scanning of data for
signatures prior to storage according to the invention;
[0041] FIG. 5 is a simplified block diagram illustrating a third
embodiment of a storage device supporting scanning of data for
signatures prior to storage according to the invention;
[0042] FIG. 6 is a simplified block diagram illustrating a fourth
embodiment of a storage device supporting scanning of data for
signatures prior to storage according to the invention;
[0043] FIG. 7 is a simplified block diagram illustrating a fifth
embodiment of a storage device supporting scanning of data for
signatures prior to storage according to the invention;
[0044] FIG. 8 is a simplified flow diagram illustrating a third
embodiment of a method for supporting scanning of data for
signatures prior to storage according to the invention;
[0045] FIG. 9 is a simplified flow diagram illustrating a fourth
embodiment of a method for supporting scanning of data for
signatures prior to storage according to the invention;
[0046] FIG. 10 is a simplified block diagram illustrating a sixth
embodiment of a storage device supporting scanning of data for
signatures prior to storage according to the invention; and,
[0047] FIG. 11 is a simplified block diagram illustrating a seventh
embodiment of a storage device supporting scanning of data for
signatures prior to storage according to the invention.
DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION
[0048] The following description is presented to enable a person
skilled in the art to make and use the invention, and is provided
in the context of a particular application and its requirements.
Various modifications to the disclosed embodiments will be readily
apparent to those skilled in the art, and the general principles
defined herein may be applied to other embodiments and applications
without departing from the scope of the invention. Thus, the
present invention is not intended to be limited to the embodiments
disclosed, but is to be accorded the widest scope consistent with
the principles and features disclosed herein.
[0049] In the following description of the various embodiments same
reference numerals are used for same components. Referring to FIG.
1a, a first embodiment of a storage device 100 supporting scanning
data for signatures prior to storage is shown. The storage device
100 comprises a port 105 for being mated to a port 155 of a host
system 150. Processor 110 of the storage device 100 communicates
via the mated ports 105 and 155 with a processor 160 of the host
system 150 for receiving first data for being stored within the
storage device 100. Upon receipt of and during scanning thereof,
the first data are stored in a temporary storage medium 115 in
communication with the circuitry 110. Further, the storage device
100 comprises memory 120 in communication with the processor 110
having stored therein executable commands for execution on the
processor 110 for communicating with the host system 150 and for
processing the first data. The temporary storage medium 115 is used
for temporary storage of other than guaranteed previously scanned
data and acts, for example, as a register of the processor 110
during: receipt of the first data; scanning of the first data; and
provision/retrieval of the first data to/from a scanned data memory
125 in communication with the processor 110. During scanning of the
first data, the processor 110 compares the first data with at least
a predetermined signature stored in signature memory 130 in
communication therewith. Optionally, the at least a predetermined
signature are received prior to receipt of the first data and
stored in the temporary storage medium 115, allowing omission of
the signature memory 130. Alternatively, the processor 110
comprises electronic circuitry designed for performing a portion of
the communication and data processing in a hardware implemented
fashion. Further alternatively, the peripheral device comprises
electronic circuitry for performing the complete communication and
data processing in a hardware implemented fashion, thus allowing
omission of the memory 120.
[0050] In the present embodiment, the interface 105 is a serial USB
interface, for example, a male USB connector, for interfacing with
a female USB port 155 of the host system 150. Alternatively, other
interfaces are used. The USB interface is advantageous, since the
USB standard is well established for connecting a computer to
peripheral devices, i.e. most present day computers comprise at
least one USB port. The storage device 100 is, for example,
implemented using readily available USB memory storage key
technology such as a Reduced Instruction Set Computing (RISC)
microprocessor, RAM 115, ROM 120, and a NAND flash memory 125.
Typically, the various components are disposed on a Printed Circuit
Board (PCB) encased in a substantially robust plastic or metal
casing making the USB memory storage key sturdy enough to be
carried in a pocket without the risk of damaging the components.
Using this technology it is possible to provide in a portable
storage device 100 a computing platform on which information is
stored and computations are performed in a secured fashion.
[0051] The invention is not limited to the present embodiment--a
portable storage device as shown in FIG. 1a--but is also beneficial
when employed, as shown in FIG. 1b, in an external hard-drive 100b
coupled to the host system 150 or a computer network and serving,
for example, as a back-up, in an internal Hard-Drive 100c disposed
inside the host system 150--shown in FIG. 1c, and in an Optical
Disk Drive 100d such as a CD or DVD Drive--shown in FIG. 1d. The
advantages of providing such storage devices with the capability
for scanning of data for signatures prior to storage will readily
become apparent to those of skill in the art when discussing
various embodiments of a method for scanning data for signatures
prior to storage according to the invention below.
[0052] FIG. 2 illustrates a simplified flow diagram of a first
embodiment of a method for scanning data for signatures prior to
storage. At 10, first data for being stored within the storage
device are received. Upon receipt the first data are stored in the
temporary storage medium 115 for storing other than guaranteed
previously scanned data--at 20. Using the processor 110 of the
storage device, the first data are compared with at least a
predetermined signature and a comparison result is determined in
dependence thereupon--at 30. In dependence upon the comparison
result--at 40--the first data are provided to the scanned data
memory 125 when the comparison result is indicative of other than a
match--at 50--or the first data are other than provided to the
scanned data memory 125 when the comparison result is indicative of
a match--at 60. There are several options at 60 for handling the
first data such as deleting the first data, repairing the data if
possible, for example, by removing the data portion resembling a
signature of a computer virus, or storing the first data in a
buffer memory 135 for storing other than guaranteed previously
scanned data of a second embodiment 200 of a storage device
according to the invention, as shown in FIG. 3. Optionally, the
processor 110 generates message data indicating that the first data
are computer virus free or a computer virus has been detected and
provides the same to the processor 160 for displaying the message
to the user. Alternatively, the storage device comprises an
indicator such as a LED, not shown, for notifying the user, for
example, by displaying different colors such as Green when the data
are computer virus free and Red when a computer virus has been
detected. Further optionally, the processor 110 stores the message
data in memory such as the buffer memory 135. This is especially
advantageous in the portable storage device 200 which comprises an
internal power source 140, such as a battery--or a rechargeable
battery--enabling storage of the first data in the buffer memory
135 and scanning of the first data after removal of the portable
storage device 200 from the host system. Here, when a computer
virus is detected, the first data are kept in the buffer memory 135
and the message data are stored, for example, together with the
first data in the buffer memory 135. This enables notification of a
user after mating the storage device 200 with a host system of the
detected computer virus and, for example, allows the user to
retrieve the file and attempt a repair using an antivirus program
on the host system.
[0053] The method illustrated in FIG. 2 is highly beneficial for
scanning the first data for signatures indicative of computer
viruses by ensuring that only guaranteed previously scanned data
are stored in the scanned data memory 125. For example, employment
of this method for storing data in portable storage devices such as
USB memory storage keys or optical disks substantially reduces the
risk that an infected file is transferred from one computer to
another, while employment of this method with Hard-Drives
substantially increases the likelihood that a computer virus is
detected.
[0054] Of course, the scanning for computer viruses is only
effective when the predetermined signatures are up-to-date.
Referring to FIG. 4, a simplified flow diagram of a second
embodiment of a method for scanning data for signatures prior to
storage according to the invention is shown. At 1, the processor
110 of the storage device sends a request for receiving at least an
updated predetermined signature to the host system 150. The request
is received by the processor 160 of the host system 150 which then
initiates establishing of a secure communication in accordance with
a secure protocol between the processor 110 and a server for
providing predetermined signatures 175 via a communication network
170 such as the Internet and port 165. Alternatively, the processor
110 sends the request via the host system 150 directly to the
server 175, omitting the processor 160. Further alternatively, the
server 175 initiates establishing of a secure communication, for
example, in predetermined intervals or when new signatures are
available. This is advantageous when the storage device is a
non-portable storage device, as shown in FIGS. 1b to 1d, ensuring
that the signatures are up-to-date. In portable storage devices,
the processor 110 sends the request, for example, after the
portable storage device 100 is mated with the host system 150 or,
alternatively, when a request from the processor 160 for storing
data is received. At 2, a secure communication between the
processor 110 and the server 175 is established. The communication
is secured using, for example, encoding such as an encryption
method. Encryption methods are divided into symmetric key
methods--secret-key cryptography--and asymmetric key
methods--Public-key cryptography. In a symmetric key method, for
example, DES and AES, the sender and receiver have a shared key set
up in advance and kept secret from all other parties; the sender
uses this key for encryption and the receiver uses the same key for
decryption. In an asymmetric key method, for example, RSA, there
are two separate keys, a public key is published and enables any
sender to perform encryption, while a private key is kept secret by
the receiver and enables only him to perform decryption.
Optionally, to further enhance security the keys are provided by a
"trusted source" 180 such as a key service provider via the
communication network 170. The received key is then, for example,
stored in the temporary storage medium 115 and after decryption of
the updated predetermined signatures--received at 3--deleted.
Alternatively, the key is stored in memory for establishing future
secure communication with the server 175. Upon receipt, the updated
predetermined signatures are stored in the signature memory 130--at
4. The steps 1 to 4 are then followed by the steps 10 to 60 shown
in FIG. 2. Optionally, the processor 110 includes in the request
data indicative of a last update of the predetermined signatures.
This is especially beneficial in portable storage devices reducing
the number of signatures to be transmitted for an update.
[0055] Referring to FIG. 5, a third embodiment 300 of a storage
device according to the invention is shown. The storage device 300
comprises an unscanned data memory 145 in communication with the
port 105. For example, the provision of the unscanned data memory
145 enables a user to quickly store the first data without scanning
or to store the first data if they contain portions similar to the
signatures. Optionally, the unscanned data memory 145 is used for
data storage and retrieval without involvement of the processor
110, thus reducing the risk of spreading a computer virus to data
stored in the scanned data memory 125.
[0056] Referring to FIG. 6, a fourth embodiment 400 of a storage
device supporting scanning data for signatures prior to storage
according to the invention is shown. The storage device 400 is of
similar structure as the storage device 100, however, the
components are disposed in two housings 400A and 400B with: the
housing 400A comprising the port 105, the processor 110, the
temporary storage medium 115, the memory 120, and the signature
memory 130; and the housing 400B comprising the scanned data memory
125. The scanned data memory 125 is in communication with the
processor 110 via mated ports 405 and 410 of the housing 400A and
400B, respectively, for receiving guaranteed previously scanned
data. Alternatively, the processor 110 comprises electronic
circuitry designed for performing a portion of the communication
and data processing in a hardware implemented fashion. Further
alternatively, the peripheral device comprises electronic circuitry
for performing the complete communication and data processing in a
hardware implemented fashion, thus allowing omission of the memory
120.
[0057] Optionally, the port 105 is a serial USB port, for example,
a male USB connector with a USB extension cable 406, for
interfacing with a female USB port 155 of the host system 150. Use
of a USB cable allows flexibility in positioning the storage device
400A. Further optionally, the ports 405 and 410 are a female and a
male USB connector, respectively. The peripheral device 400 is, for
example, implemented using commonly available USB memory storage
key technology. Furthermore, it allows implementation of the
housing 400B and its components using off-the-shelf USB memory
sticks.
[0058] Referring to FIG. 7, a fifth embodiment 500 of a storage
device supporting scanning data for signatures prior to storage
according to the invention is shown. The storage device 500 is of
similar structure as the storage device 400 with the components
being disposed in two housings 500A and 500B. The housing 500A
comprises the port 105, the processor 110, the temporary storage
medium 115, the memory 120, and the signature memory 130, and the
housing 500B comprises the scanned data memory 125. The housing
500A is disposed inside a housing of the host system 150 and
connected to a bus system 185 such as a serial bus of the host
system 150 via port 105. The housing 500A further comprises an
external port 505 for mating with port 510 of the housing 500B for
providing communication between the processor 110 and the scanned
data memory 125. Optionally, the external port 505 is omitted and
communication between the scanned data memory 125 and the processor
110 is enabled via the port 105, the bus system 185 and the port
155 of the host system 150 having the port 510 of the housing 500B
mated thereto. Alternatively, the processor 110 comprises
electronic circuitry designed for performing a portion of the
communication and data processing in a hardware implemented
fashion. Further alternatively, the peripheral device comprises
electronic circuitry for performing the complete communication and
data processing in a hardware implemented fashion, thus allowing
omission of the memory 120.
[0059] For example, the housing 500A comprises a PCB, which is
inserted into an expansion slot of the host system 150 and has an
interface for connection to a USB bus system, while the housing
500B and its components are implemented using off-the-shelf USB
memory sticks.
[0060] Another significant security challenge, especially for large
organizations such as government departments and larger
corporations, has arisen due to the increasing storage capacity of
USB memory storage keys. Their small size and ease of use allows
unsupervised visitors or unscrupulous employees to smuggle
confidential data with little chance of detection.
[0061] The following embodiments of a method for scanning data for
signatures prior to storage according to the invention provide a
solution to this significant security problem. Referring to FIG. 8,
a simplified flow diagram of a third embodiment of a method for
scanning data for signatures prior to storage according to the
invention is shown. It is noted that this embodiment is
beneficially employed with the storage devices according to the
invention as illustrated above. Here, the capability of the storage
devices to scan received data for signatures is exploited by
inserting pieces of a security code called "security signatures"
into sensitive data. In its simplest form, a same security
signature is implanted at one location in the data. The location
is, determined, for example, by an authorized person such as a
system administrator or on a substantially random basis.
Alternatively, a plurality of, possibly different, signatures are
inserted in the data, thus increasing security.
[0062] At 70, a storage device according to the invention sends
data indicative of a capability for scanning received data for
signatures. The data are received by the processor 160 of the host
system 150 and processed. At 71, when the processor 160 identifies
a scanning capability of the storage device, first data are
provided thereto--at 74 , otherwise the processor performs
instructions other than providing the first data--at 76--such as
generating a message prompting the user to use a storage device
having the scanning capability. The process for performing the
steps 70 to 76 is, for example, stored in a storage medium having
stored therein executable commands for execution on the processor
160 of the host system 150. At 78, the first data for being stored
are received at the storage device. Upon receipt the first data are
stored in the temporary storage medium 115 for storing other than
guaranteed previously scanned data--at 80. Using the processor 110
of the storage device, the first data are compared with at least a
predetermined security signature indicative of a security level and
a comparison result is determined in dependence thereupon--at 82.
In dependence upon the comparison result--at 84--the first data are
provided to the scanned data memory 125 when the comparison result
is indicative of other than a match--at 86--or the first data are
other than provided to the scanned data memory 125 when the
comparison result is indicative of a match--at 88. For example, at
88 the received first data are deleted from the temporary storage
medium 115. Optionally, the processor 110 generates--at 90--message
data indicating that the first data have been stored or prevented
from storage and provides the same to the processor 160 for
displaying the message to the user. Alternatively, the storage
device comprises an indicator such as a LED, not shown, for
notifying the user, for example, by displaying different colors
such as Green when the data have been stored and Red when the data
have been prevented from storage.
[0063] The method illustrated in FIG. 8 is optionally highly
beneficial for scanning the first data for security signatures by
ensuring that sensitive data or data of a predetermined security
level are prevented from storage in a storage device.
[0064] Referring to FIG. 9, a simplified flow diagram of a fourth
embodiment of a method for scanning data for signatures prior to
storage according to the invention is shown. Again, it is noted
that this embodiment is beneficially employed with the storage
devices according to the invention as illustrated above. Here too,
the capability of the storage devices to scan received data for
signatures is exploited by inserting pieces of a security code
called "security signatures" into sensitive data. To increase
flexibility a plurality of different signatures, each associated
with a predetermined level of security, are inserted in the
respective data. Inserting different signatures associated with
different levels of security allows differentiating, for example,
between users having different levels of security or between users
belonging to different departments of an organization.
[0065] The fourth embodiment of the method, as shown in FIG. 9,
starts with the same steps 70, 71, and 76 for identifying if the
storage device has a scanning capability and prevents the data from
storage if the scanning capability is missing. At 72, the processor
110 of the storage device receives authorization data indicative of
a security level of a user of a host system 150 in communication
with the storage device. Optionally, the authorization data are
received in an encoded fashion from the host system. For example,
the authorization data are encoded using an encryption method, as
discussed above. Alternatively, the authorization data are hashed.
The processor 110 then selects--at 73--in dependence upon the
authorization data predetermined security signatures corresponding
to security levels above a security level of the user for the
comparison process at 82. The step 73 is then followed by the same
steps 74 to 90 as shown in FIG. 8. As is evident, this embodiment
substantially increases flexibility by allowing storage of data
according to a user specific security level. For example, board
members of a large organization are enabled to store data of the
highest security level while directors are prevented from storing
such data but are enabled to store mid security level data and
other staff is prevented from storing data of any of these security
levels. Furthermore, it is possible to differentiate between data
belonging to various departments of a large organization such as
research, sales, human resources, etc.
[0066] The following steps 91 to 95 of the fourth embodiment are
highly beneficial by preventing access to sensitive data stored in
a portable storage device by an unauthorized person, for example,
when the portable storage device has been lost, stolen, or
misplaced. At 91, the processor 110 of the storage device receives
second authorization data indicative of a second security level of
a user of a host system 150 in communication with the storage
device. The processor 110 then compares--at 92--the second
authorization data with the security level of the first data stored
in the scanned data memory 125. For example, after storage of the
first data the processor 110 generated data indicative of the
security level of the user and stored the same together with the
first data or, alternatively, stored the selected predetermined
signatures together with the first data. If the second security
level is below the security level of the first data, the processor
110 prevents access to the first data--at 93. If the second
security level is one of equal to the security level of the first
data and higher than the security level of the first data, the
first data are provided from the scanned data memory 125--at 94.
Alternatively, the data are provided only when the second security
level matches the security level of the first data. Optionally, the
processor 110 generates--at 95--message data indicating that the
first data are accessible or prevented from access and provides the
same to the processor 160 for displaying the message to the user.
Alternatively, the storage device comprises an indicator such as a
LED, not shown, for notifying the user, for example, by displaying
different colors such as Green when the data are accessible and Red
when the data are prevented from access.
[0067] Referring to FIG. 10, a sixth embodiment of a storage device
for supporting scanning of data for signatures prior to storage
according to the invention is shown. Here, the storage device 600
is of similar structure as the device shown in FIG. 1a, but
additionally comprises a biometric input device 605 in
communication with the processor 110 for determining a user
authorization according to the fourth embodiment of a method for
scanning data for signatures prior to storage according to the
invention is shown. Alternatively, the biometric input device is
implemented in other storage devices according to the invention in
a similar fashion. In operation, the processor 110 provides the
biometric input data to a processor 160 of a host system 150 for
determining a security level of the user in dependence thereupon
and receives authorization data from the processor 160 of the host
system 150. Optionally, the biometric input data are sent and the
authorization data are received in an encoded fashion. For example,
the biometric input data and the authorization data are encoded
using an encryption method, as discussed above. Alternatively, the
biometric input data and the authorization data are hashed.
Alternatively, using the processor 110 of the storage device 600,
the biometric input data are compared with biometric data
indicative of a user stored in memory of the storage device 600 and
a security level of the user is determined in dependence thereupon.
This enables processing of the provided biometric input data as
well as the sensitive stored data indicative of a user within a
single portable housing, thus the efficacy of tampering is
substantially reduced.
[0068] As above, the storage device 600 is, for example,
implemented using readily available USB memory storage key
technology. Furthermore, biometric input devices such as contact
fingerprint imagers are also readily available in a compact fashion
suitable for disposing in a USB memory storage key housing. The
peripheral device 600 provides a biometric input device 605
together with memory for storing sensitive data indicative of a
user, a processor 110 for determining user authorization, and
scanned data memory 125 for storing data in dependence upon user
authorization in a single compact housing suitable for carrying in
a pocket.
[0069] Optionally, user authorization using biometric input data is
used for determining a security level of a user prior retrieval of
the data stored in the scanned data memory 125.
[0070] Referring to FIG. 11, a seventh embodiment of a storage
device for supporting scanning of data for signatures prior to
storage according to the invention is shown. Here, the storage
device 700 is of similar structure as the device shown in FIG. 6,
but additionally comprises a biometric input device 705 implemented
in a first housing 700A and in communication with the processor 110
for determining a user authorization according to the fourth
embodiment of a method for scanning data for signatures prior to
storage according to the invention is shown. In operation, the
processor 110 provides the biometric input data to a processor 160
of a host system 150 for determining a security level of the user
in dependence thereupon and receives authorization data from the
processor 160 of the host system 150. Optionally, the biometric
input data are sent and the authorization data are received in an
encoded fashion. For example, the biometric input data and the
authorization data are encoded using an encryption method as
discussed above. Alternatively, the biometric input data and the
authorization data are hashed. Alternatively, using the processor
110 of the storage device 700 in housing 700A, the biometric input
data are compared with biometric data indicative of a user stored
in memory of the storage device and a security level of the user is
determined in dependence thereupon. Optionally, the storage device
700 comprises a second processor 710 in the second housing 700B for
receiving second authorization data indicative of a second security
level of a user and for comparing the second security level of the
user with data indicative of the security level of the first data
stored in the scanned data memory 125 which are stored, for
example, together with the first data in the scanned data memory
125. Employment of the processor 710 is highly beneficial by
preventing access to sensitive data stored in the scanned data
memory 125 of the portable storage device 700B by an unauthorized
person, for example, when the portable storage device 700B has been
lost, stolen, or misplaced.
[0071] The storage device 700 is, for example, implemented using
readily available USB memory storage key technology, allowing
implementation of the housing 700B and its components using
off-the-shelf USB memory sticks. Furthermore, biometric input
devices such as various types of fingerprint imagers, cameras for
retinal scans or face recognition, or microphones for voice
recognition are also readily available together with software for
processing the biometric information and are implementable in the
peripheral device 700A.
[0072] Obviously, one skilled in the art will readily arrive at
numerous combinations of the various embodiments of the method and
storage device for supporting scanning of data for signatures prior
to storage according to the invention in order to satisfy specific
needs in different applications.
[0073] Numerous other embodiments of the invention will be apparent
to persons skilled in the art without departing from the spirit and
scope of the invention as defined in the appended claims.
* * * * *